1. Field of the Invention
The present invention relates generally to dot array recorders (i.e., printers) for recording waveforms and the like, wherein the dot array recorders have a dot array printing head in which the dot printing elements are arranged in a row. More particularly, the present invention relates the such dot array recorders which include a LED (light emitting diode) array having a plurality of LED's corresponding to the group of dot printing elements which are illuminated as to indicate the position of the printing.
2. Setting for the Invention
When using thermal array recorders or electrostatic recorders, which have no recording pen, it often becomes necessary to be capable of indicating the position of the waveforms to be printed such as for purposes of adjusting the reference line for recording, or the sensitivity of the recorder.
With prior art type dot array recorders whose dot array printing heads are equipped with LED arrays which correspond with the groups of printing elements, the user is thereby enabled to recognize the printing position in such printers. With such printing heads, the LEDs are arranged as densely as possible, e.g., at a 1 mm pitch over the entire length, e.g., 200 mm, of the thermal head. In consequence, although the position of the waveform can be indicated with high accuracy due to the small pitch of the arrangement of the LEDs, the apparatus as a whole becomes very expensive and uneconomical to manufacture.
In addition, since it is rather difficult to discriminate the lighting position, the user who wishes to adjust the reference line for the recording or setting the sensitivity of the recorder, has to actually drive the recorder to print the reference signal on the recording paper and to adjust the printer such that the position of the printed reference signal coincides with the position of the reference line.
Accordingly, an object of the present invention is to provide a device for indicating the position of a waveform to be recorded using a dot array recorder, wherein the reference position adjustment can be easily conducted on the LED array surface, while reducing the number of the LEDs required to achieve the same.
Another object of the present invention is to provide a device for indicating the waveform position of a dot array recorder which does not require the user thereof to actually drive the recorder to print the reference signal on the recording paper, or adjust the printer such that the position of the printed reference signal coincides with the position of the reference line.
Other and further objects of the present invention will be explained hereinafter and will be more particularly delineated in the appended claims, and other objects of the present invention will, in part, be obvious hereinafter to one with ordinary skill in the art to which the present invention pertains, and will, in part, appear obvious hereinafter.